Coupling



Jan. 27, 1948.

L."w. wlGHrM'AN comimue rma Feb.`11. 1946 nur Y His Attorney.

Patented Jan. 27, l1948 I COUPLING Lawrance W. Wightrnan, Fort Wayne, Ind., alsignorto General Electric Company, a corporation o! New York application February n, 194e. serai No. asses 15 clams. (ci. 17a-zw improved magnetic couplings without the use of frictional clutching surfaces.

A further object of my invention is to provide improved magnetic couplings with an arrangement for a direct mechanical connection under high torque conditions.

Further objects and advantages of my invention will become apparent and my invention will be better understood from the following descrip; tion referring to the accompanying drawing, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming part of this specification. 4

In the drawing, Fig. l is a sectional side elevational view of an embodiment of my improved coupling construction; Fig. 2 is a plan view of the coupling shown in Fig. 1; and Fig. 3 is a sectional side elevational view of another embodiment of my invention.

Referring to the drawing, I have shown an einbodiment of my improved coupling construction provided with a coupling member I of magnetic material having a central longitudinally extending hub or bushing portion 2 of nonmagnetic material and provided with a plurality of circumferentially spaced teeth 3 on an outer radial face of a radially spaced ring portion 4 which surrounds and is mounted on the central hub portion 2 by an integral outwardly extending web portion 5. A substantially toroidal magnet 6 is mounted in'the coupling member I on the hub portion 2 and may be of any suitable construction, such as a permanent magnet having poles of opposite polarity at the two axial longitudinally spaced ends thereof. With a permanent magnet 6 arranged to excite the coupling members magnetically, Iprovide a casing I having a nonmagnetic material substantially cylindrical side portion and an end of magnetic material forming a cup arranged around the permanent magnet l and secured in position in any suitable manner,

the portion I I and is radially spaced and secured to the hub portion III by an integral web portion I3. With the permanent magnet excitation of the coupling members described above, the teeth 3 will be polarized at one magnetic polarity and the teeth I2 will be polarized at the opposite magnetic polarity, the magnetic circuit being from the magnet l to the central annular polar portion I0 of coupling member 9, web portion Il, radial' face II, teeth I2, teeth I, ring portion l of coupling member I, and web portion l back tothe permanent magnet 8. The teeth I2 are made substantially the same in number and size as the teeth 3 of the coupling member I, so that for a given position, the magnetic poles formed by the teeth 3 and I2 of the couplingvmembers will be substantially in axial alignment to provide for the lowest reluctance in the magnetic circuit of the other coupling member.

In this coupling construction, torque is adapted to be transmitted from one coupling member to the other without the use of frictional engagement surfaces, and, therefore, it is necessary that the adjacent surfaces of the two couplingmembers I ,and 9 be held in axially spaced relationship. This is obtained by providing a bearing in the central part of both of the coupling members and arranging a thrust pin for maintaining the members in spaced relation. In the illustrated construction, the coupling member I is mounted on and supported by a shaft Il to which it is secured in any suitable manner. as by a setscrew I5, and the coupling member 9 is mounted on and supported by a shaft I8, to which it is secured in any suitable manner, as by a setscrew I1. The shaft I4 is formed with a central bearing opening or socket I8 having a bearing portion I9, and the shaft I6 is formed with a central bearing opening or socket 20 which is internally threaded and in which a. central bearing member 2i is secured by as by brazing, welding, or by being staked in y position as shown at 8. A second coupling member 9 of magnetic material is formed with a cen tral annular polar portion I0 and an outer ring portion Il formed with a plurality of circumferentially spaced teeth I2 in the radial face of ing thrust pin' 22 extends into both of the bearing sockets and engages the bearings. and 2|, so as to maintain the adjacent surfaces of the coupling members I and 9 at a predetermined desired axial spacing. This air gap spacing between the two coupling members may be adjusted by adjusting the position of the bearing member 2| within the threaded bearing socket 20 in the be found that an abnormally high starting torquev 3 is required to be transmitted through the coupling, and the magnetic forces between the two coupling members may not be adequate to provide the transmittal of this high torque, and a positive mechanical connection is required which will be operative only under such conditions. In the illustrated arrangement, a notch or socket 23 is formed in the radial face of the coupling member 9, and a dog 24 of nonmagnetic material is secured in the radial face of the other coupling member and arranged to extend into the notch 23; such that under normal operating conditions, the dog 24 is spaced midway between the sides of the notch 23 out of engagement with these sides, and the notch 23 is formed of such a size relative to the size of the dog 24 to provide for an angular displacement between the teeth 3 and I2 of the two coupling members to permit these teeth to move to a position so that the teeth of one member are substantially midway between the teeth on the other coupling member before one side of the dog 24 engages a side of the notch or socket 23. Under high torque transmission conditions, however, the dog 24 engages a side of the notch 22 and the relative sizes of these two mechanical driving parts of the two coupling members are made such that when a mechanical driving connectigin s made, the teeth on one of the coupling members is substantially midway between the teeth on the other coupling members, with the teeth on the dog-carrying member l having a slightly larger gap from adjacent the teeth i2 on the notched coupling member 8 on the side thereof corresponding tothe side of the dog in engagement with a side of the notch 23 than the gap between the teeth 3 on the dog carrying member and adjacent teeth I2 on the notched member on the side of the dog not in engagement with a side of the notch, thereby providing a position of the teeth for a maximum transmission of torque through the magnetic forces between these teeth in addition to a direct mechanical driving engagement between the dog 24 and the side of the notch 23.

In Fig. 3 of the drawing I have shown another embodiment of my invention in which both of the coupling members are provided with exciting magnets 25 and 26 which may be permanent magnets similar to that shown in Fig. 1. These magnets 25 and 2i are mounted in coupling members 21 and 28 of magnetic material which are adapted to be supported on shafts 23 and 30 by nonmagnetic central bushings 3i and 32 secured to the shaft in any suitable manner, as by keys 33 and 34 and setscrews 35 and I6, respectively. These coupling members 21 and 28 are formed similar to the coupling members in Fig. 1 with circumferentially extending ring portions 31 and I! with circumferentially spaced teeth 33 and 4l in the adjacent radial faces thereof. If desired, the magnets 25 and 2B also may be provided with pole faces 4l and 42 of magnetic materialwhich may be secured in any desired manner to the magnets 25 and28 and to the nonmagnetic bushing members 3| and 32. In this construction, the two coupling members are adapted to be axially spaced with an air gap between the adjacent poles thereof by providing a central bearing in the central part of both of the members to be coupled together. This spacing may be obtained by a construction similar to that shown in Fig. 1 or by simpler arrangement, such as that shown in this gure, in which the shafts 28 and III are formed with bearing sockets 43 and 44 with a thrust pin 4i seated in these two bearing sockets 42 and 44 and made ot such a length as to provide the desired air gap between the adjacent' pole faces of the two coupling members. Furthermore, as in the arrangement shown in Fig. 1 it may be desired for certain types of couplings to provide a positive mechanical drive between the two coupling members under abnormally high torque conditions, and this is provided by permitting a relative circumferential displacement of the teeth 3l and 40 of the two coupling members so that they become substantially opposite the slots between the teeth for a maximum transmission of torque by the magnetic forces between these teeth, and a dog 4| is secured in the radial face of one oi' the coupling members and extends into a socket 41 in the radial face of the other coupling member. As in the arrangement shown in Fig. l, the relative sizes of the dog 43 and the slot or notch 41 are such as to permit the abovementioned maximum circumferential displacement between the teeth of the two members before the dog 48 contacts a side of the socket or notch 41, thereby providing for the maximum transmission of torque by the magnetic forces between the teeth in addition to a direct mechanical driving engagement between the dog 4l and the side of the socket 41. In some installations, it may be found desirable to provide a plurality of these direct mechanical driving dOg and socket arrangements and these may be spaced circumferentially around the periphery of the two coupling members. In either of the two constructions shown, the direct mechanical driving arrangement may be omitted so that the maximum torque which can be transmitted through the coupling will definitely be limited by the slippge between the two coupling members dependent on the maximum magnetic forces which can be exerted between the teeth of the two coupling members when these teeth are displaced substantially midway between each other.

While I have illustrated and described a particular embodiment of my invention, modincations thereof will occur to those skilled in the art. I desire it to be understood, therefore. that my invention is not to be limited to the particular arrangement disclosed, and I intend in the appended claims to cover all modifications which do not depart from the spirit and scope oi my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A coupling including a member of magnetic material with a central portion having a plurality of circumferentially spaced teeth on the outer radial face oi a radially spaced ring portion connected to said central portion by an integral outwardly extending web portion, a second coupling member of magnetic material with a central portion and an outer ring portion with circumferentially spaced teeth on the radial face thereof substantially the same in number and size as said first-mentioned coupling member teeth `spaced radially from said central portion and connected thereto by an integral web portion. a magnet mounted on said first named coupling member and polarized axially whereby the teeth of said first named coupling member are polarized at a polarity opposite from the teeth of said second named coupling member. and nonmagnetic axial thrust means for maintaining said coupling giembers in predetermined axially spaced rela- 2. A coupling including a member of magnetic material with a central portion having a pluralby an integral portion, a'magnet mounted in said iirst named coupling member between said central and teeth portions and polarized axially whereby the teeth of said rst named coupling member are polarized at a polarity opposite from the teeth of said second named coupling member,

and axial thrust means for maintaining said coupling members in predetermined axially spaced relation.

3. A coupling including a member oi' magnetic material with a central portion having a plurality oi circumferentially spaced teeth on the outerk radial face of a radially spaced ring portion connected to said central portion by an integral outwardly extending web portion, a second couplingr member of magnetic material with a central portion and an outer ring portion with circumferentlaliy spaced teeth on the radial face thereof sub stantially the same in numberand size as said first-mentioned coupling member teeth spaced radially from said central portion and connected thereto by an integraliweb portion, a magnet mounted on said nrst named -coupling vmember and polarized axially whereby the teeth of said ilrst named coupling member are polarized at a polarity opposite -from the teeth of said second named coupling member, a central bearing in said first-mentioned coupling member. a central bearing insaid second coupling'member, and meansv including a thrust pin engaging both of said bearings for maintaining said coupling members 'at a predetermined axial spacing.

4. A coupling including a member of magnetic material with a central portion having a plurality of circumferentially spaced teeth on the outer radial face of a radially spaced surrounding ring portion connected to said central portion by an integral outwardly extending web portion, a secondfcoupling memberv of magnetic material axially spaced from said iirst-mentioned f coupling member witha central portionA and an outer ring portion with circumierentially spaced teeth on the radial face thereof substantially the same in number and size as said first-mentioned. coupling member teeth spaced radially from said central portion and connected thereto by an integral web portion, a magnet mounted on said first named coupling member and polarized axially whereby the teeth of said first named coupling member are polarized at a polarity opposite from the teeth of said second named coupling member, and axial thrust means for maintaining said coupling members in predetermined axially spaced relation.

5. A coupling including a member or magnetic material with a. central portion having a plurality of circumferentially spaced teeth on the outer radial face o! a radially spaced ring portion connected to said central portion by an integral outwardly extending web portion, a magnet on said coupling member,'a second coupling member oi' magnetic material with a central portion and an outer ring portion with circumferentially spaced teeth on the radial face thereof substantially the Y same in number and size as said mst-mentioned coupling member teeth spaced radially from said s t central portion and connected thereto by an in'- tegral webfportion. means for supporting said ilrst-mentioned coupling member including a member having a central bearing opening therein, means for supporting said second coupling member including a second supporting member 'having a central bearing opening therein. and

means including a thrust pin extending into both of said bearing openings and engaging bearing surfaces therein for maintaining said coupling members at a predetermined axial spacing.

'6. A coupling including a member of magnetic material with a central portion having a plurality of circumferentially spaced teeth radially spaced and connected to said central portion by an integral portion, a second coupling member of magnetic material with a central portion and a plurality oi circumierentially spaced teeth connected to said central portion by an integral portion, a. magnet mounted on said first named coupling member and polarized axially whereby the `teeth of said ilrst named'coupling member are torque transmission conditions witha relative p0' sitioning of said teeth on one of said coupling members substantially midway between the teeth on the other of said coupling members.

7. A coupling including a member of magnetic material with' a central portion having a plurality of circumierentially spaced teeth on the outer Aradial face of a radially spaced surrounding centrai portion by an` integral outwardly extending web portion, ai substantially toroidal magnet mounted in said coupling member between said central hub and ring portions, a second coupling member of magnetic material axially spaced frmn said inst-mentioned coupling member with a centrai portion and an outer ring portion with circumierentially spaced' teeth'on the radial face thereof substantially the same in number and size as said rst-mentioned coupling member teeth spaced radially yfrom-"said central portion and connected thereto by an integral web portion, means for supporting saidAfirst-mentioned coupling member including a. member having a central bearing openingtherein, meansjfor supporting said second coupling member including a second supporting memberhaving a central bearing opening therein, and means including a thrust pinextending into both of said bearing yopenings andv engaging bearing surfaces therein for maintaining said coupling members at a predetermined axial spacing.

8. A coupling including a member of magnetic material with a central portion having a plurality of circumferentially spaced teeth radially spaced Hon said first named coupling member and polarized axially whereby the teeth of said iirst named coupling member are polarized at a polarity opposite from the teeth of said second named coupling member, axial thrust means for maintaining said coupling members at a predetermined axial spacing, a notch in one of said coupling members, and a dog of nonmagnetic material in the other of said coupling members extending into said notch and being of a size re1- ative to said notch to provide for mechanical engagement "oi said dos with a side of said notch substantially only under high torque transmission conditions with a relative positioning of said teeth on one of said coupling members substantially midway between the teeth on the other of said coupling members for maximum torque transmission between said coupling omembers by a direct mechanical drive therebetween through said dog and by magnetic forces between said teeth.

9. A` coupling including a member of magnetic material with a central portion having a plurality of circumferentially spaced teeth radially spaced and connected to said central portion by an integral outwardly extending portion, a second coupling member of magnetic material with a central portion and circumferentially spaced teeth thereon substantially the same in number as said first-mentioned coupling member teeth and connected to said central portion by an integral portion, a magnetmounted on said nrst named coupling member and polarized axially whereby the teeth of said ilrst named coupling member are polarized at a polarity opposite from the teeth of said second named coupling member, a central bearing in said mst-mentioned coupling member, a central bearing in said second coupling member, axial thrust means engaging both of said bearings for maintaining said coupling members at a predetermined axial spacing, a notch in one of said coupling members, and a dog of nonmagnetic material in the other ot said coupling members extending into said notch and being of a size relative to said notch to provide for mechanical engagement of said dog with a side of said notch substantially only under high torque transmission conditions with a relative positioning of said teeth on one of said coupling members substantially midway between the teeth on the other of said coupling members for maximum torque transmission between said coupling members by a direct mechanical drive therebetween through said dog and by magnetic forces between said teeth.

l0. A coupling including a member of magnetic material with a central portion having a plurality of circumferentlally spaced teeth on a radially spaced portion connected to said central portion by an integral outwardly extending web portion. a second coupling member of magnetic material with a central portion and an outer portion with circumierentially spaced teeth thereon substantially the same in number as said first-mentioned coupling member teeth and connected thereto by an integral web portion, a magnet mounted on said first named coupling member and polarized axially whereby the teeth o! said iirst named coupling member are polarined at a polarity opposite from the teeth rof said second named coupling member, a central bearing in said first-mentioned coupling member, a central bearing in said second coupling member, means enpaging both of said bearings for maintaining said coupling members at a predetermined axial spacing. a notch in one of said coupling members. and a dog of nonmagnetic material in the other oi' said coupling members extending into said notch and being of a size relative to said notch transmission between said coupling members b! a direct mechanical drive therebetween said dog and by magnetic forces between said teeth.

il. A coupling including a member ot metio l material with a central portion having a plm-ality ot circumferentially spaced teeth on the outer radial face of a radially spaced surrounding ring portion connected to said central portion by an integral outwardly extending web portion. a substantially torcidal magnet mounted in said coupling member between said central and ring portions, a second coupling member of magnetic material axially spaced from said first-mentioned coupling member with a central portion and an outer ring portion with circumrerentially spaced teeth on the radial face thereof substantially the same in number and size as said first-mentioned coupling member teeth spaced radially from said central portion and connected thereto by an integral web portion, means for supporting said first-mentioned coupling member including a `member having a central bearing opening therein,

means for supporting said second coupling member including a second supporting member having a threaded central bearing opening therein. an adjustable central bearing threadedly secured in said threaded central bearing opening of said second coupling supporting member for adjusting the spacing between the bearings in said supporting members, and means including a thrust pin extending into both oi said bearing openings and engaging bearing surfaces therein for maintaining said coupling members at a predetermined axial spacing.

12. A coupling including a member o! magnetic material with a central portion having a plurality oi circumierentially spaced teeth on the outer radial face of a radially spaced ring portion connected to said central portion by an integral outwardly extending web portion. a magnet on said coupling member, a second coupling member oi magnetic material with a central portion and an outer ring portion with circumi'erentially spaced teeth on the .radial iace thereof substantially the same in number and sise as said first-mentioned coupling member teeth and connected thereto by anintegral webportiomacentralbearingin said mst-mentioned coupling member, a central bearing in said second coupling member, means includingathrustpinengagingbothofsaidbearings for maintaining said coupling members at apredeterminedaxialspacinmanotchinoneol said coupling members. and a dog oi nonmagnetic material in the other of said coupling members extending intosaid notehandbeingotasilerelative to said notch to provide for mechanical engagement or said dog with a side of said notch under high torque on conditions Iwith a relative positioning of said teeth on one ot said coupling members substantially midway between theteethontheotherofsaidcouplingmembers for maximum torque on between said coupling members by a direct mechanical drive therebetween through said dog and by magnetic forces between said teeth.

13. A coupling including a member ot magnetic material with a central portion having a plurality or circumi'ercntiallyspacedteethonthe cuter radial face of a radially spaced ring portion connected to said central portion by an integral outwardly extending web portion, a magnet on said coupling member between said central and ring portions, a second coupling member of magnetic material with a central portion and an outer ring portion with circumferentially spaced teeth on the radial face thereof substantially the same in number and size as said first-mentioned coupling member `teeth spaced radially from said central portion and connected thereto by an integral web portion, a central bearing in said first-mentioned coupling member, a central bearing in said second coupling member, means engaging both of said bearings for maintaining said coupling members at a predetermined axial spacing, a notch in o-ne of said coupling members, and a dog in the other of said coupling members extending into said notch and being of a size relative to said notch to provide for mechanical engagement of said -dog with a side of said notch under high torque transmission conditions with a relative positioning of said teeth on one of said coupling members substantially midway between the teeth on the other of said coupling members with the teeth of said dogcarrying member having a slightly larger gap from adjacent teeth on said notched member on the side thereof corresponding to the side of said dog in engagement with a side of said notch than the gap between the teeth of said dog-carrying member and adjacent teeth of said notched member on the side' of said dog not in engagement with a side of said notch providing for maximum torque transmission between said coupling members by a direct mechanical drive therebetween through said dog and by magnetic forces between said teeth. y

14. A coupling including a. member' of magnetic material with a central portion having a plurality of circumferentially spaced teeth on the outer radial face of a radially spacedring portion connected to said central portion by an integral outwardly extending web portion, a magnet on said coupling member between said central and j ring portions, a second coupling member of magnetic material with a central portion and an outer ring portion with circumferentiaily spaced teeth on the radial-face thereof substantially the same in number and size as said first-mentioned coupling member teeth spaced radially from said central portion and connected thereto by an integral web portion, means for supporting said first-mentioned coupling member including a member having a central bearing. means for supporting said second coupling member including a second supporting member having a central bearing, means engaging both of said bearings for maintaining said coupling members at a predetermined axial spacing, a notch in the radial face of one of said coupling members` and a dog in the other of said coupling members extending into said notch and being of a size relative to said notch to provide for mechanical engagement of said dog with the sides of said notch under high torque transmission conditions with a rela tive positioning of said teeth on one of said coupling members substantially midway between the teeth on the other of said coupling members with the teeth of said dog-carrying member having a slightly larger gap from adjacent teeth on said notched member on the side thereof correspondlng to the side of said dog in engagement with a side of said notch than the gap between the teeth 10 of said dog-carrying member and adjacent teeth of said notched member on the side of said dog not in engagement with a side of said notch providing for maximum torque transmission-between said coupling members by a direct mechanical drive therebetween through said dog and by magnetic forces between said teeth.

15. Av coupling including a member of magnetic material with a central hub portion having a plurality of circumferentially spaced apart teeth on theouter radial face'of a surrounding ring portion connected to said hub by an integral outwardly extending web portion, a substantially toroidal magnet mounted in said coupling member between said hub and ring portions, a second coupling member 0f magnetic material axially spaced from said first-mentioned coupling member with a central portion and an outer ring portion with circumferentialiy spaced apart teeth on the'radial face thereof substantially the same in number and size as said lirst-mentioned coupling member teeth spaced radially from said central portion and connected thereto by an integral web portion, means for supporting said rst-mentioned coupling `member includingA a member having a central bearing opening therein. means for supporting said second coupling member including a`second supporting member having a threaded central bearing opening` therein. an adjustable central bearing threadedly secured in said threaded central bearing opening'of said second coupling supporting member for adjusting the spacing between the bearings in said supporting members. means including a thrust pin extending into both ci said bearing openings and engaging bearing surfaces therein for maintain- -ing said coupling members at a predetermined axial spacing, a notch in the radial face of one of said coupling members, and a dog of nonmagi netic material in the other nf said coupling members extending into said notch and having a space between the sides of said dog and sides of said notch to provide for mechanical engagement of said dog with the sides of said notch under high torque transmission conditions providing a relative positioning of said teeth on one of .said coupling members substantially midway between the teeth on the other of said coupling members with the teeth of said dog-carrying member having a`slightly larger gap from adjacent teeth on said notched member on the side thereof corresponding to the side of said dog in engagement with a side of said notch than the gap between the teeth of said dog-carrying member and adjacent teeth of said notched member on the :side of said dog not in engagement with a side of said notch piioviding for maximum torque transmission between said coupling members by a direct mechanical drive therebetween through said dog and by magnetic forces between said teeth.

LAWRANCE W. WIGHTMAN.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS 

